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This study aims to investigate the wetting behavior of AgCuTi and AgCu filler metals on selective laser melting (SLMed) Ti/TiB₂, and to analyze the microstructure and fracture characteristics of SLMed Ti/TiB₂/AgCuTi or AgCu alloy/SLMed Ti/TiB₂ brazed joints. The wetting behavior of AgCuTi and AgCu filler metals on the selective laser melted (SLMed) Ti/TiB₂ has been studied. The analysis of microstructures and fracture characteristics in vacuum-brazed SLMed Ti/TiB₂ substrate, using AgCuTi and AgCu filler metals, has been conducted to elucidate the influence of brazing temperature and alloy composition on the shear strength of the brazed joints.

Brazing SLMed-Ti/TiB₂ in a vacuum using AgCuTi and AgCu filler metals, this study aims to explore the optimal parameters for brazed joints at various brazing temperatures (800°C−950°C).

The findings suggest that elevated brazing temperatures lead to a more extensive diffusion region in the joint as a result of the partial melting of the filler metal. The joint composition changes from distinct Ti₂Cu layer/TiCu layer/filler metal to a-Ti (ss) + ß-Ti (ss)/TiCu. As the brazing temperature increases, the fracture mode shifts from brittle cleavage to ductile fracture, mainly attributed to a decrease in the CuTi within the brazed joint. This change in fracture behavior indicates an improvement in the ductility and toughness of the joint.

The originality of this study lies in the comprehensive analysis of the microstructure and shear strength of vacuum brazing SLMed Ti/TiB₂ using AgCuTi and AgCu filler metals.

This study aims to investigate the influence mechanism of brazing and aging on the strengthening and corrosion behavior of novel multilayer sheets (AA4045/AA7072/AA3003M/AA4045).

Polarization curve tests, immersion experiments and transmission electron microscopy analysis were used to study the corrosion behavior and tensile properties of the sheets before and after brazing and aging.

The strength of the sheet is weakened after brazing due to brittle eutectic phases, and recovered after aging due to enhanced precipitation strengthening in the AA7072 interlayer. The core of nonbrazed sheets cannot be protected due to the significant galvanic coupling effect between the intermetallic particles and the substrate. Brazing and aging treatments promote the redissolved of second phased and limit corrosion along the eutectic region in the clad, allowing the core to be protected.

AA7xxx alloy was added to conventional brazed sheets to form a novel Al alloy composite sheet with AA4xxx/AA7xxx/AA3xxx structure. The strengthening and corrosion mechanism of the sheet was proposed. The added interlayer can sacrificially protect the core from corrosion and improves strength after aging treatment.

The purpose of this paper is to compare corrosion behavior of a modified multilayer material with Cu before and after brazing process.

Sea water acidified accelerated tests (SWAATs), potentiodynamic polarization tests and scanning electron microscopy were used to study the corrosion behavior and macro/micro structures. Results indicate that the corrosion mechanisms of the sheets before and after brazing process are completely different.

The un-brazed material is uniform corrosion, while the brazed material has a high sensitivity to localized corrosion and loses cathodic protection to the core. It is found that brazing process causes copper transition from the core alloy into eutectic phases in the cladding, leading to higher E_corr and different potential distribution compared with those of un-brazed materials.

For the modified multilayer material after brazing, there are two stages of corrosion. First, corrosion attack takes place along eutectic phases in the cladding material, and then core alloy dissolves by forming a galvanic couple with the nobler residual cladding.

This paper aims to investigate the effect and mechanism of O atom single doping, Ce and O atoms co-doping on the interfacial microscopic behavior of brazed Ni-Cr/diamond.

Using first-principles calculations, the embedding energy, work of separation, interfacial energy and electronic structures of Ni-Cr-O/diamond and Ni-Cr-O-Ce/diamond interface models were calculated. Then, the effect of Ce and O co-doping was experimentally verified through brazed diamond with CeO₂-added Ni-Cr filler alloy.

The results show that O single-doping reduces the interfacial bonding strength between Ni-Cr filler alloy and diamond but enhances its interfacial stability to some extent. However, the Ce and O co-doping simultaneously enhances the interfacial bonding strength and stability between Ni-Cr filler alloy and diamond. The in-situ formed Ce-O oxide at interface impedes the direct contact between diamond and Ni-Cr filler alloy, which weakens the catalytic effect of Ni element on diamond graphitization. It is experimentally found that the fine rod-shaped Cr₃C₂ and Cr₇C₃ carbides are generated on diamond surface brazed with CeO₂-added Ni-Cr filler alloy. After grinding, the brazed diamond grits, brazed with CeO₂-added Ni-Cr filler alloy, present few fracture and the percentage of intact diamond reaches 67.8%. Compared to pure Ni-Cr filler alloy, the brazed diamond with CeO₂-added Ni-Cr filler alloy exhibit the better wear resistance and the slighter thermal damage.

Using first-principles calculations, the effect of Ce and O atoms co-doping on the brazed diamond with Ni-Cr filler alloy is investigated, and the calculation results are verified experimentally. Through the first-principles calculations, the interface behavior and reaction mechanism between diamond and filler alloy can be well disclosed, and the composition of filler alloy can be optimized, which will be beneficial for synergistically realizing the enhanced interface bonding and reduced thermal damage of brazed diamond.

The purpose of this paper is to investigate the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Al₂O₃ particles and 10 wt% NaCl solution are used to evaluate erosion and corrosion resistance of WC-Ni vacuum brazed coating. Combined test of erosion and corrosion is also conducted. The microstructure of each specimen is characterized by the scanning electron microscopy. The chemical composition was determined by energy-dispersive X-ray spectroscopy.

WC-Ni vacuum brazed coating layer is effective protective coating under combined erosion and corrosion environment. The weight loss of coating layer is more reduced as the cumulative test time.

WC-Ni vacuum brazed coatings are investigated to check characteristic of the combined erosion and corrosion environment. WC-Ni vacuum brazed coatings are kind of diffusion coating that attract attention because of the resistance of superb impact and corrosion in comparison with other coatings. Some previous researches reported the properties of vacuum brazed WC material. Erosion and corrosion behaviors of WC-Ni vacuum brazed coatings were studied in our previous research, respectively. Hence, in this research, the principal objective is to examine the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

This paper outlines a method of sequentially joining steel laminations together using a high strength brazed joint to produce laminated tools. Individual joints were produced by using a heated platen rather than a furnace. Lap shear test samples were used to evaluate the tensile strengths of bonded laminates. Two laminate gauges were tested, 0.8mm and 1.6mm. Ranging trials were undertaken to determine optimum time to produce the joint. Constants for the trials were platen temperature, laminate material, braze material, joint area and joining pressure. At optimum conditions, that is the least time taken for highest tensile strength, the 0.8mm laminate averaged a strength of 4.7kN in 120 seconds’ heating time and the 1.6mm laminate averaged 9.3kN in 210 seconds.

A METHOD of joining pipes which does not make use of heavy bulky fittings has always been required in the aircraft industry. In addition, as aircraft speeds increase well into the supersonic range, the need for more reliable joints that will withstand even more rigorous working conditions becomes apparent.

This paper details the development of a rapid tooling manufacturing route for the gravity and high‐pressure die‐casting industries, resulting from an EPSRC funded collaborative research project between the Universities of Warwick, Loughborough and DeMontfort, with industrial support from, amongst others, MG Rover, TRW Automotive, Sulzer Metco UK Ltd and Kemlows Diecasting Products Ltd. The developed process offers the rapid generation of mould tools from laser‐cut laminated sheets of H13 steel, bolted or brazed together and finish machined. The paper discusses the down‐selection of materials, bonding methods and machining methods, the effect of conformal cooling channels on process efficiency, and the evaluation of a number of test tools developed for the industrial partners. The paper also demonstrates the cost and time advantages (up to 50 and 54 per cent, respectively) of the tooling route compared to traditional fabrication methods.

Wolverhampton‐based IMI Marston, a wholly owned subsidiary of IMI plc, employs over 500 personnel in five product groups. Its highly successful Aerospace Heat Transfer Group designs and manufactures heat exchangers for a wide marketplace and for a variety of applications. Looks at the increasing complexity of avionics equipment, and the need to dissipate heat in order to maintain a stable operating environment and examines the design, material and process selection in developing materials and products for this sector.